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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

28118 results found.

  1. GRB 090424 : Multiband Optical observation from Nainital
  2. GRB 090426: R-band limit
  3. GRB 090424: Continued R-band monitoring
  4. GRB 090423: CARMA mm observations
  5. GRB 090423: millimeter detection
  6. GRB 090425: Fermi GBM detection
  7. GRB 090426: VLT spectroscopy
  8. GRB 090426: GROND Observations of the Optical/NIR Afterglow
  9. GRB 090426: Near infrared observation with ISLE at OAO
  10. GRB 090426: Okayama MITSuME optical observation
  11. GRB090426 Swift/UVOT observations
  12. GRB 090426 Keck LRIS redshift
  13. GRB 090426: Swift-XRT refined analysis
  14. GRB 090423: GROND second epoch imaging and refined SED
  15. Detection of bright radio afterglow of GRB 090424 with the VLA
  16. GRB 090426: Enhanced Swift-XRT position
  17. GRB090426: Observation for Optical counterpart from MIRO
  18. GRB 090426: inspection of SDSS images
  19. GRB 090426: Swift detection of a burst with an optical counterpart
  20. GRB090424: R-band detection (37.5 hrs post-burst), jet break?
  21. GRB 090424: MASTER-Net prompt optical limit
  22. GRB 090424: WHT ISIS spectroscopy
  23. VLA radio observation of high-z GRB 090423
  24. GRB090424: BVRI/R-band detection after 15 hrs burst
  25. GRB 090424 : Lulin 1m telescope optical observations
  26. GRB 090424: THO optical observations
  27. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  28. GRB090423: Y-band limit
  29. GRB 090424 Gemini-South Redshift
  30. GRB 090424 : TAOS optical detection
  31. GRB 090424 optical observations
  32. GRB 090424: Liverpool Telescope observations
  33. GRB 090424: Swift-XRT refined analysis
  34. GRB 090424: Optical observations from 1.23m CAHA
  35. GRB 090423: energetic, luminosity and jet break
  36. Swift/UVOT observations of GRB 090424
  37. GRB 090424: Enhanced Swift-XRT position
  38. GRB 090424: TNT optical observations
  39. GRB 090424: Swift detection of a burst with an optical counterpart
  40. GRB 090423: Refined TNG analysis
  41. GRB 090423 limiting magnitudes
  42. GRB 090423: VLT/ISAAC spectroscopy
  43. GRB 090423: Near infrared observation at Okayama Observatory
  44. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  45. GRB 090423: TNG Amici spectrum
  46. GRB 090423: GROND detection and preliminary photo-z
  47. GRB 090423: NOT z-band limit
  48. GRB 090423: Correction to NIR photometry
  49. GRB 090423: Swift-XRT refined analysis
  50. GRB090418A Rc-band photometry
  51. GRB090423 - Swift/UVOT upper limits.
  52. GRB 090423: NIR photometry and evidence for spectral break
  53. GRB 090422: Swift-XRT refined analysis
  54. GRB 090423: UKIRT data further analysis
  55. GRB 090423: Enhanced Swift-XRT position
  56. GRB 090422: Swift/UVOT Upper Limits
  57. GRB 090423: UKIRT K-band observations
  58. GRB 090423: P60 Observations
  59. GRB 090423: Faulkes Telescope South observations
  60. GRB 090418A: R and I band observation
  61. GRB 090423: Swift detection of a burst
  62. GRB 090422: Liverpool Telescope possible candidate
  63. GRB 090422: Enhanced Swift-XRT position
  64. GRB 090418A: RTT150 optical observations
  65. GRB 090422: Liverpool Telescope observations
  66. GRB 090422: Swift detection of a burst
  67. GRB 090418C: Fermi GBM Detection
  68. GRB 090418A: Swift/UVOT Detection of the Neighbouring Galaxy
  69. Swift-BAT trigger 349718 is not a burst
  70. GRB 090417B: Optical observation
  71. GRB 090418A: optical observations
  72. GRB 090419: Swift/UVOT Observations
  73. GRB 090418A: Swift/UVOT Observations
  74. GRB 090417B: Swift/UVOT Upper Limits
  75. GRB 090417B Correction to the BAT refined analysis position
  76. GRB 090419: Swift-XRT refined analysis
  77. GRB 090419: GROND detection of afterglow candidate
  78. GRB 090418: Optical observations with MITSuME Okayama and Ishigaki 1m telescope
  79. VLA radio detection of GRB 090418
  80. VLA radio upper limit on GRB 090417B
  81. GRB 090419: Enhanced Swift-XRT position
  82. GRB 090418: Swift XRT refined analysis
  83. GRB 090418A: ROTSE-III Refined Analysis
  84. GRB 090419: Swift detection of a burst
  85. GRB 090418B: Detection of a bright burst from Swift-BAT slew data
  86. GRB 090417B: Gemini imaging
  87. GRB 090417B: Galaxy redshift
  88. GRB 090417B: Swift-XRT refined analysis
  89. GRB 090418: Enhanced Swift-XRT position
  90. GRB 090418: PAIRITEL NIR detection
  91. GRB 090418 Lick Redshift
  92. GRB 090418: Swift detection of a burst with optical afterglow
  93. GRB 090417B: Subaru NIR Observations
  94. GRB 090417B: Liverpool Telescope observations
  95. GRB 090417B: MITSuME Okayama optical upper limits
  96. GRB090417B: Xinglong TNT optical upper limit
  97. GRB 090417B: optical observations
  98. GRB090417B: optical observations
  99. GRB 090417B: Swift detection of a burst
  100. GRB 090417: Swift detection of a short burst

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